The invention relates to a heat exchanger, in particular charge air cooler or exhaust gas cooler for an internal combustion engine of a motor vehicle and method for manufacturing it.
Heat exchangers which are embodied as what are referred to as all-aluminum heat exchangers are already known. It is also known that such heat exchangers or all aluminum heat exchangers can be used as charge air coolers for an internal combustion engine. Known charge air coolers have two boxes which are spaced apart and are fluidically connected by means of a large number of pipes, such as flat pipes. The charge air to be cooled then flows from one of the two boxes through the pipes into the other of the two boxes. Intermediate spaces through which a coolant can flow are provided between the pipes, transversely with respect to the direction of their longitudinal extent. The pipe block which is formed by these pipes is surrounded here by a separate piece of sheet metal which is closed circumferentially around the pipe block and forms a cover or casing so that a chamber is formed between the two boxes through which chamber the pipes run. This casing is provided with an inflow and outflow for coolant.
In such configurations it is known that charge air coolers which are configured as all-aluminum heat exchangers each have a box and a base on one side of the pipe block. The box forms here a type of hood which is closed on its open side by the base. A plurality of through-openings into which the pipes are inserted are provided here in the base. The base/bases are therefore also referred to as pipe plate/plates. The pipes are generally inserted into these bases before the respective bases are joined to the boxes which are respectively assigned to them. In configurations of this type, on the one hand the pipes are connected to the bases and, on the other hand the bases are connected to the boxes using suitable connecting means. It is known, for example, for the pipes to be soldered to the bases and for the bases to be soldered to the boxes.
In the prior art, DE 10 2006 043 526 A1 discloses a heat exchanger which has a pipe block and a base at the respective ends of the pipe block and a box which is fitted onto the respective base, wherein the bases and the boxes are soldered to one another. It is also known for the bases to be able to run in or over the box. For this purpose, the bases have, for example, a circumferential edge which projects in the longitudinal direction of the longitudinal axes of the pipes and which engages from the outside around the box end facing the base or is plugged into the box in the region of this box end. In this context, this projecting edge of the base is soldered to the box.
Further embodiments of such boxes in which a separate base is not provided and which have merely one box are also known. In such embodiments, the pipes are widened in their end regions facing the respective box and are soldered to one another in the widened regions.